EPR studies of the isolated negatively charged silicon vacancies in -type 4- and 6-SiC; Identification of symmetry and silicon sites

Mizuochi, Norikazu*; Yamasaki, Satoshi*; Takizawa, Haruki; Morishita, Norio; Oshima, Takeshi; Ito, Hisayoshi; Isoya, Junichi*

Physical Review B, 68(16), p.165206_1 - 165206_11, 2003/10

https://doi.org/10.1103/PhysRevB.68.165206

Isolated silicon vacancies with negative charge (V) in 4H- and 6H-SiC were studied using EPR. The samples used in this study were irradiated with electron at 3 MeV at RT. After irradiation, the samples were annealed at 300 C in Ar to eliminate C-related isolated vacancies. As the result of C hyperfine spectra, two kinds of V(I) and V(II) were distinguished and they are assigned to be arising from hexagonal and cubic sites of Si. In addition, both V(I) and V(II) signals have C symmetry, which means nearest-neighbor carbon atoms silightly distorted from a regular tetrahedron.